1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 /* Copyright (c) 2015-2018, The Linux Foundation. All rights reserved.
4  * Copyright (C) 2018-2022 Linaro Ltd.
5  */
6 #ifndef _GSI_PRIVATE_H_
7 #define _GSI_PRIVATE_H_
8 
9 /* === Only "gsi.c" and "gsi_trans.c" should include this file === */
10 
11 #include <linux/types.h>
12 
13 struct gsi_trans;
14 struct gsi_ring;
15 struct gsi_channel;
16 
17 #define GSI_RING_ELEMENT_SIZE	16	/* bytes; must be a power of 2 */
18 
19 /**
20  * gsi_trans_move_complete() - Mark a GSI transaction completed
21  * @trans:	Transaction whose state is to be updated
22  */
23 void gsi_trans_move_complete(struct gsi_trans *trans);
24 
25 /**
26  * gsi_trans_move_polled() - Mark a transaction polled
27  * @trans:	Transaction whose state is to be updated
28  */
29 void gsi_trans_move_polled(struct gsi_trans *trans);
30 
31 /**
32  * gsi_trans_complete() - Complete a GSI transaction
33  * @trans:	Transaction to complete
34  *
35  * Marks a transaction complete (including freeing it).
36  */
37 void gsi_trans_complete(struct gsi_trans *trans);
38 
39 /**
40  * gsi_channel_trans_mapped() - Return a transaction mapped to a TRE index
41  * @channel:	Channel associated with the transaction
42  * @index:	Index of the TRE having a transaction
43  *
44  * Return:	The GSI transaction pointer associated with the TRE index
45  */
46 struct gsi_trans *gsi_channel_trans_mapped(struct gsi_channel *channel,
47 					   u32 index);
48 
49 /**
50  * gsi_channel_trans_complete() - Return a channel's next completed transaction
51  * @channel:	Channel whose next transaction is to be returned
52  *
53  * Return:	The next completed transaction, or NULL if nothing new
54  */
55 struct gsi_trans *gsi_channel_trans_complete(struct gsi_channel *channel);
56 
57 /**
58  * gsi_channel_trans_cancel_pending() - Cancel pending transactions
59  * @channel:	Channel whose pending transactions should be cancelled
60  *
61  * Cancel all pending transactions on a channel.  These are transactions
62  * that have been committed but not yet completed.  This is required when
63  * the channel gets reset.  At that time all pending transactions will be
64  * marked as cancelled.
65  *
66  * NOTE:  Transactions already complete at the time of this call are
67  *	  unaffected.
68  */
69 void gsi_channel_trans_cancel_pending(struct gsi_channel *channel);
70 
71 /**
72  * gsi_channel_trans_init() - Initialize a channel's GSI transaction info
73  * @gsi:	GSI pointer
74  * @channel_id:	Channel number
75  *
76  * Return:	0 if successful, or -ENOMEM on allocation failure
77  *
78  * Creates and sets up information for managing transactions on a channel
79  */
80 int gsi_channel_trans_init(struct gsi *gsi, u32 channel_id);
81 
82 /**
83  * gsi_channel_trans_exit() - Inverse of gsi_channel_trans_init()
84  * @channel:	Channel whose transaction information is to be cleaned up
85  */
86 void gsi_channel_trans_exit(struct gsi_channel *channel);
87 
88 /**
89  * gsi_channel_doorbell() - Ring a channel's doorbell
90  * @channel:	Channel whose doorbell should be rung
91  *
92  * Rings a channel's doorbell to inform the GSI hardware that new
93  * transactions (TREs, really) are available for it to process.
94  */
95 void gsi_channel_doorbell(struct gsi_channel *channel);
96 
97 /* gsi_channel_update() - Update knowledge of channel hardware state
98  * @channel:	Channel to be updated
99  *
100  * Consult hardware, change the state of any newly-completed transactions
101  * on a channel.
102  */
103 void gsi_channel_update(struct gsi_channel *channel);
104 
105 /**
106  * gsi_ring_virt() - Return virtual address for a ring entry
107  * @ring:	Ring whose address is to be translated
108  * @index:	Index (slot number) of entry
109  */
110 void *gsi_ring_virt(struct gsi_ring *ring, u32 index);
111 
112 /**
113  * gsi_trans_tx_committed() - Record bytes committed for transmit
114  * @trans:	TX endpoint transaction being committed
115  *
116  * Report that a TX transaction has been committed.  It updates some
117  * statistics used to manage transmit rates.
118  */
119 void gsi_trans_tx_committed(struct gsi_trans *trans);
120 
121 /**
122  * gsi_trans_tx_queued() - Report a queued TX channel transaction
123  * @trans:	Transaction being passed to hardware
124  *
125  * Report to the network stack that a TX transaction is being supplied
126  * to the hardware.
127  */
128 void gsi_trans_tx_queued(struct gsi_trans *trans);
129 
130 #endif /* _GSI_PRIVATE_H_ */
131